1. Anything by Isaac Asimov
Fun, easy to read, yet philosophically interesting and meaningful science fiction.
The Foundation Series, especially, is awesome.
2. Anything by Ann Coulter
She’s beautiful, funny, sharp, insightful, thoughtful, and poignant. She’s primarily known for being a political commentator, but I think she’s generally a brilliant thinker. Overall, Ann Coulter is one kickass woman and her writing reflects that.
3. Ayn Rand
Ayn Rand has a lot of critics. But I really like a lot about her philosophy of objectivism, and I think her books have something interesting and worthwhile to say and understand about society.
I’ll add more books that I recommend as they come to mind.